<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <style>
        div{
            width: 300px;
            height: 300px;
            background-color: pink;
        }
    </style>
</head>
<body>
    <div id="dv"></div>
    <div id="dv1"></div>
    <script>
        // document.body.addEventListener('touchmove',function(e){
        //     for (var i = 0; i< e.changedTouches.length; i++){
        //         console.log(e.changedTouches[i].identifier);
        //     }
        // })
        // console.log(dv)
        var dv = document.getElementById('dv')
         dv.addEventListener('touchmove',function(e){
            //  console.log(e);
            for (var i = 0; i < e.changedTouches.length; i++){
                console.log(e.changedTouches[i].identifier);
            }
         })   

         dv1.addEventListener('touchmove',function(e){
             console.log(e);
            for (var i = 0; i < e.changedTouches.length; i++){
                console.log(e.changedTouches[i].identifier);
            }
         })   

         // 只有触摸屏才会有触摸事件。
    </script>
</body>
</html>